Daniela Fasano explains the Poka Yoke approach to becoming a lean assistant
As many of you may already know, Lean Management and Lean Thinking are principles and techniques derived from the Toyota Production System, established around 70 years ago and now widely adopted across industries worldwide.
The lean concept can be applied in any business and production process. The two main pillars of Lean methodology are:
- Respect for people
- Continuous improvements
Lean methodology is about continuously improving work processes, purposes, and people. Shared responsibility and shared leadership are encouraged by lean management, because a brilliant idea or initiative can be generated at any level of the company’s organization, despite hierarchy. In such a supporting and trusting environment, people who are doing the job can say how it should be done, with a huge positive impact on the company’s overall performance.
The term Poka Yoke (poh-kah yoh-keh) means ‘mistake-proofing’ or, more literally, avoiding (yokeru) inadvertent errors (poka), and was coined in Japan during the 1960s by Shigeo Shingo, an industrial engineer at Toyota. The initial term was baka-yoke, meaning ‘fool-proofing’, but this was later changed because of the term’s connotation being too dishonorable and offensive for Japanese culture.
Poka Yoke is seen as one of the most valuable takeaways from the lean concept: it has become one of the most powerful work standardization techniques.
Examples of Poka Yoke in our everyday lives include the switch of the automatic car that requires the vehicle to be in “Park” or “Neutral” before it can be started and the washing machine that does not start if the door is not closed properly, in order to prevent flooding.
These actions are “behaviour-shaping constraints” and this way over time our behaviour is set by repetition and habit.
Poka Yoke is any mechanism that helps to avoid mistakes: it is universally applicable and has proven to be a true efficiency booster.
In a nutshell, Poka Yokes help people work right, making mistakes (almost) impossible to happen: their benefit is undeniable.
Similarly, the “tricks” we have learned, experimented with or developed as Assistants to prevent or avoid mistakes not only in our daily tasks but also in our Managers’ professional lives can be seen as Poka Yoke. This can include ensuring that the right conditions exist before a process is executed, and when this is not possible, becoming a detective and tackling all obstacles, thus improving our quality and reliability as well as our Executive’s performance.
Now that we are fully aware of this technique, we can use it whenever we realize that a mistake could occur or something could go wrong.
The Poka Yoke Technique
1. Identify the operation or process.
2. Ask “why?” five times and analyze the ways a process can fail.
3. Choose the right Poka Yoke approach, such as using a shutout type (preventing an error being made), or an attention type (highlighting that an error has been made).
4. Take a comprehensive approach instead of thinking of Poka Yokes just as a limit switch or automatic shutoff.
5. Determine whether a contact (use of shape, size or other physical attributes for detection), constant number (error triggered if a certain number of actions are not made), or a sequencing method (use of a checklist to ensure completing all process steps) is most appropriate. (these points need a liberal interpretation in our role).
6. Test the method and see if it works.
7. Train the “operator”, review performance and measure success.
It is said that the Poka Yoke technique is like a diamond set in the crown of Lean Management…and I add that that diamond is an Assistant’s best friend!